Textile finishing composition comprising a methoxymethyl melamine and an aliphatic alcohol having at least eight carbon atoms



Patented Sept. 2, 1947 TEXTILE FINISHING COMPOSITION COM- PRISING AMETHOXYMETHYL MELAMINE AND AN ALIPHATIC ALCOHOL HAVING AT LEAST EIGHTCARBON ATOMS John Marshall Grim, New York, N. Y., assignor to AmericanCyanamid Company, New York, N. Y., a corporation of Maine No Drawing.Application February 7, 1942, Serial No. 429,955

8 Claims.

This invention relates to the treating and finishing of textiles andtextile-forming materials. The invention includes processes forfinishing textiles, textile finishing compositions, the preparation ofsuch textile finishing compositions, and textiles of improved propertiesfinished with the compositions and by the processes of the invention.

Textile fabrics, yarns, threads and fibers have been heretofore treatedwith a wide variety of creaseproofing agents, waterproofing agents,materials to prevent shrinking, felting, fulling, etc., lubricants,softening agents, sizes, binding agents and other materials to improvethe appearance and feel or hand of the goods. The treatment of textilesfor these and similar purposes is known as textile finishing, and theagents employed for this purpose are known as textile finishing agents.It i a principal object of the present invention to provide textilefinishing compositions and methods for their preparation and applicationto textiles, which compositions and methods will produce finishedtextiles having a greatly improved water resistance, a more desirablehand, creaseresistance, a very much reduced tendency for shrinking andother desirable improvements which will be apparent from the descriptionwhich follows. Other important objects will appear hereinafter.

The various textile materials which may be treated in accordance with myinvention include fibers, thread, yarns, knit and woven cloth, and

- other fabricated materials of cotton, linen, hemp,

jute, regenerated cellulose, cellulose esters, cellulose ethers, wool,synthetic wool, silk, synthetic silk and other fibrous materials whethernatural or synthesized. Hereinafter and in the claims for purposes ofbrevity all of these various textile-forming materials and structurescontaining the same will be referred to as textile fabrics.

Although textile fabrics having a greatly reduced tendency to shrink aswell as crease-resistance and an improved hand may be obtained bytreatment with aqueous dispersions of alkylated methylol melaminefollowed by drying and curing the resin in the fabric, fabrics sotreated have but a. fair resistance to the penetration of water andtherefore leave much to be desired insofar as their water-repellentcharacteristics are concerned. By treatment of textile fabrics withcompositions such as will be presently described I am enabled to retainall of the advantages of shrink-resistance, crease-resistance, improvedhand, etc. which are obtainable by treatment of the fabric with loweralkylated methylol melamines and in addition impart to such fabrics avery high degree of water-repellency.

My improved textile finishing process includes the steps of treatingtextile fabrics such as mentioned above with dispersions of alkylatedmethylol melamine and a higher aliphatic alcohol followed by drying andcuring these resin-forming constituents on the fabric. For example, Imay treat the textile fabric with an aqueous dispersion containingapproximately 10 parts of methylated methylol melamine and 1.5 parts ofoctadecyl alcohol followed by an appropriate heat treatment. Theimproved results which I obtain are due, I believe, to certain chemicalreactions which take place during the drying and curing treatmentbetween the alkylated methylol melamine and the higher alcohol.

When a textile fabric treated with a methylated methylol melamine havinga structure such as a W N CHaOCH2 N N 01120 CH3 is subjected to a heattreatment the methylated methylol melamine polymerizes, or cures, in thefabric. Curing of the resin takes place by splitting off one or moremolecules of methyl alcohol followed by a molecular rearrangement whichfavors polymerization. While, as stated before, fabrics so treated havea very marked resistance to shrinking, a good hand, crease-resistanceand other important characteristics the fabrics are not particularlywater-repellent. This lack of water-resistance is due in part at leastto the fact that the polymerized resin molecule has no effectivehydrophobic groups available to repel water. In other words the curedresin is fairl easily wetted and water is allowed to penetrate into theinterstices of the fabric. By adding to the alkylated methylol melaminetextile treating composition a higher aliphatic alcohol and thenimpregnating, drying and curing the fabric under conditions presently tobe described I believe that a chemical reaction takes place between the'alkylated methylol melamine and higher alcohol which modifies the natureof the cured resin yet does not materially influence thepolymerization-mechanism necessary to obtain a permanentwater-insoluble, cured resin in the fabric.

This reaction, which is in the nature of an ether interchange probablytakes place between the methylated methylol melamine to produceintermediate compounds having the probablestructure:

H\ /N\ H Il' cmocH, N N CHzOCmHu n-tr-cmo on, I in which at least one ofthe short chain CHa-- groups is replaced with a long chain alkyl group.It will also be noted that the above compound also contains at least onemethoxymethyl group which at the temperature of the curing process cansplit off methanol allowing a molecular rearrangement to take placewhich favors polymerization with other alkylated methylol melaminemolecules. The long chain alkyl residue of the higher alcohol is notsplit off at the temperature of the curing process. The polymerizedcompound is of course water-insoluble and the long alkyl chain attachedtheretorenders the resin hydrophobic and water-repellent. It is to beclearly understood that the above discussion is merely a suggestedmechanism of what takes place in my finishing process and I do notintend to be bound thereby since regardless of whatever theory may beadvanced the superior results obtained by my process remain as adistinct advance in the art.

From the above considerations it will be seen that I may employ anyalkylated methylol melamine having at least two alkylated methylolgroups, one for reaction with the higher aliphatic alcohol and the otherproviding a point at which polymerization may proceed. I may, of course,employ alkylated methylol melamines having more than two alkylatedmethylol groups and ordinarily do so.

It should also be understood that my invention in its broader aspects isnot limited to the use of methylated methylol melamines as illustratedabove. Alkylated methylol melamines having short chain alkyl groups ofnot more than 4 carbon atoms such as ethylated, isopropylated andbutylated methylol melamines may also be employed but require greatercare in the curing steps, Ethyl alcohol and butyl alcohol split offduring the curing steps with greater diificulty and a proper cure ismore difiicult to obtain without employing temperatures which mightdamage the fabric.

The alkylated methylol melamines which I employ are prepared by knownmethods. Methylated methylol melamine may, for example, be prepared byreacting 2 to 6 moles of formaldehyde with 1 mole of melamine to form acondensation product believed to be mostly methylol melamine.

' This product is then reacted with 2 to 6 moles of methanol wherebymethylated methylol melamine is formed. By the term methylated methylolmelamine I intend to include all of these various reaction productscontaining from 2 to 6 methylated methylol groups per molecule.Excessive polymerization should be avoided during the preparation sincethe resin is preferably employed'by me in the form of an aqueousdispersion, or solution, and products polymerized excessively tend to bedifficultly soluble in water.

I have also found that excessive polymerization of the product tends togive the fabrics a stiff hand. I V I The higher alcohols which I add tomy new textile finishing composition are those primary,

4 secondary and tertiary aliphatic alcohols havin at least 8 carbonatoms per molecule in order that the cured resin in the fabric willpossess hydrophobic characteristics suflicient to impart to the textilefabric a high degree of water resistance. I have for example employedalcohols such as ethyl hexanol dodecanol, tetradecanol, hexadecanol,octadecanol and the like. A particular- 1y advantageous higher alcoholsuitable for use in my textile finishing composition because of its lowcost is a commercially obtainable mixture of higher alcohols known tothe trade as Lorol" which consists predominantly of lauryl alcohol withsmaller percentages of both higher and lower aliphatic alcohols.

Although the structural formula given above indicates that one mole, oreven more, of the higher alcohol may be employed with each mole ofalkylated methylol melamine I have found that it is not necessary to usesuch a high proportion of higher alcohol to obtain satisfactorywaterproofing of textile fabrics. In general, I have found that thewater-resistant characteristics of the treated fabrics do not improveappreciably when more than 5 parts of higher alcohol is used with each10 parts by weight of the alkylated methylol melamine. Ordinarily Iemploy about 1.5 parts by weight of the higher alcohol for each 10 partsby weight of the methylated melamine in my finishing composition.Smaller proportions of the higher alcohol may be used with, however, adecrease in the water-resistance of the treated fabric. One-half part byweight of the higher alcohol for each 10 parts by weight of thealkylated methylol melamin will form 'a finishing composition capable ofrendering most textile fabrics fairly water-resistant. All theadvantages of shrink-resistance, crease-resistance, improved hand, etc.obtained by treatment with methylated methylol melamine alone are ofcourse imparted to the fabric as a result of my treatment whether theproportion -of higher alcohol be either high or low in the finishingcomposition.

The alkylated methylol melamine-higher alcohol composition which Iemploy in my process is ordinarily, and preferably, applied to thecellulose fabrics in the form of an aqueous dispersion containing fromabout 2-15% or more of the above materials. These dispersions may beprepared by simply stirring a suitable amount of the higher alcoholdissolved in a solvent such as ethyl alcohol,'isopropyl alcohol, etc.into an aqueous disperson of the alkylated methylol melamine, bothsolutions being preferably at temperatures of F. to F. Dispersing agentsmay be used such as sodium isopropyl naphthalene sulfonate, dioctylsodium sulfosuccinate, ammonium caseinate, gelatine, glue, gum arabic,etc. The preparation of these dispersions is illustrated in greaterdetail in the specific examples. The dispersions may be applied to thefabrics in various ways known to those in the art; thus, for example,the dried fabrics to be treated may be immersed in the .resin dispersionand then passed through suitable rolls as in a padder or mangle tosecure uniform impregnation and to remove excessive resin. The fabric,however, may be impregnated by other methods such as by spraying or withsuitable boxes located on the mangle. My invention is not limited to anyparticular method of impregnating the fabrics and other methods willoccur to those skilled in the art.

The amount of my alkylatedmethylol mel amine-higher aliphatic alcoholfinishing composition which may be applied to fabrics may varyconsiderably depending upon the nature of the fabric treated and theparticular finish desired. Fabrics of wool, silk, cotton, etc. may berendered water-repellent and substantially resistant to shrinkage by theapplication of from about 2 to 8% by weight of the resin-formingconstituents based on the dry weight of the fabric. Smaller amounts downto 0.5% may be used with less effective results. Larger amounts as forexample 8-14% by weight of the fabric will increase the water repellencyof the fabric and also impart thereto a high degree ofcrease-resistance. With particular types of fabrics and to secureparticular results it may be desirable to use larger amounts of. myfinishing composition up to 30% by weight of the alkylated methylolmelamine-higher aliphatic alcohol mixture as based on its weight in thefinishing composition. After the fabric has been impregnated it is driedand the fabric heated at elevated temperatures to polymerize the resin.

In order to speed up the curing of the resin and decrease the heatingtime a suitable catalyst may be added to the aqueous finishingcomposition. Oxalic acid, diammonium hydrogen phosphate and methyl acidpyrophosphate are particularly good for this purpose. other catalystssuch as triethanolamine phthalate, zinc chloride, acetic acid, mineralacids such as hydrochloric acid and others may also be used. Othercatalysts for the curing of alkylated methylol mel amine resins are knowto chemists in the resin art and may be employed.

The curing temperatures are in general quite low anad may varyconsiderably from about 200 F. to about 300 F. with a correspondingreduction in time of cure with increase of temperature. The drying andcuring operation is flexible and may be varied to suit the equipmentavailable to the processes. High temperatures of the order of 280 F. to300 F. will cure the resin to a suitably water-insoluble state in threeor four minutes. Where facilities are not available for curing the resinat moderate temperatures within the range of about 240280 F. the fabricafter being impregnated with the desired amount of my finishingcomposition may be framed to width on a pin tenter, dried, batched upona shell and allowed to stand hot to obtain a total drying and heatingtime suflicient to dry the cloth and insolubilizing the resin in thefabric. With some fabrics a drying and curing time of two or three hoursmay be required at 200 F. Drying and curing times will also depend tosome extent upon the effectiveness of the particular acceleratoremployed and upon the nature of the fabric.

After the fabric has been treated as described it should, particularlyin the case of woolen goods, be iven a short mild soaping which rendersit soft and pliable. The fabric may then be given other usual finishingtreatments such as decatizing, brushing, sheering, pressing, etc. Myprocess may be employed with both colored and uncolored goods withoutappreciably afiecting the color or shade and without damage to thematerial.

My invention will now be illustrated in detail by the following specificexamples which show: representative compositions included herein and thewater-repellent efiects obtained thereby. It should be understood,however, that although these examples may describe some of the morespecific details of the invention they are given primarily forillustrative purposes and the invention in its broader aspects is notlimited thereto.v

Example 1 960 parts by weight of formalin (37% by weight 01-120) and 252parts by weight of melamine were charged into a reaction vessel fittedwith an 9.81-- tator, thermometer, and reflux condenser and arranged sothat it could be placed under a. vacuum and heated. The contents of thereaction vessel were heated in one-half hour to a temperature of 62 C.and the pH adjusted to 1.5 with 2 normal NaOH. After heating for anotheronehalf hour, a vacuum of 28 inches of mercury was applied and themixture concentrated by removal of water. After 40 minutes heating atapproximately 54 C. the heat and vacuum were removed and 1000 parts byweight of methyl alcohol containing enough 2 normal HaPO4 to neutralizethe 2 normal NaOH added previously. The mixture at a pH of 6.4 was thenheated to distill ofi an azeotropic mixture of methanol and water,anhydrous methanol being continuously added to replace the distillate.After heating in this way for about 6 to 7 hours, one part of thedistillate would tolerate parts of toluol and the resin was considereddried. It was then concentrated under a vacuum of 28 inches of mercuryto a solids content of approximately 80%.

25 parts of the above-described 80% methylated methylol melamine, 20parts of a 5% solution of sodium isopropyl naphthalene sulfonate andparts of water were mixed and heated to approximately 100 F. -3 parts byweight of octadecyl alcohol dissolved in 48 parts by weight of isopropylalcohol and having a temperature of 80-l00 F. was poured into themethylated meth ylol melamine solution while stirring. A stabledispersion of fine particle size was obtained. To this dispersion wasthen added diammonium hydrogen phosphate in the amount of 4% based onthe total resin solids.

Samples of 80 x 80 cotton percale were then impregnated with thisdispersion by the dip and nip process, regulating the take-up so thatthe fabric contained approximately 11.5% by weight of the methylatedmethylol melamine-octadecyl alcohol constituents. The impregnated fabricwas then dried and cured for seven minutes at 290 F. The treated clothsamples were then given a short soaping for hour at F. in a soapsolution, rinsed and dried. Other samples of the treated fabric weresoaped at 160 F. in a .5% soap solution for four hours and 6 hours inorder to establish the permanency of the water-repellent finish. Stillother samples were cleaned in Stoddard solvent for two hours and fourhours at room temperatures to determine the stability of the finish todry-cleaning. The samples were then subjected to a standardizedwater-repellency test.

The water repellency test was conducted as follows: A 6 inch square ofthe cloth treated with the finishing composition was suspended 10 inchesfrom a horizontal spray nozzle supplied with water at 80 F. under ahydraulic head of exactly 6 feet. The cloth was sprayed for one minuteduring which time 1.5 gallons of water were discharged through thenozzle. The cloth samples were then dried for 10 seconds, rolled betweenpieces of absorbent paper to remove surface water, and then weighed. Theincrease of weight was expressed as percent water absorbed, based on theoriginal dry weight of the cloth. An un- 7 treated sample of the clothabsorbed from 90-100% of its weight of water. The results of these spraytests are as follows:

Moisture Absorption in Per cent Dry Cleaned in Stoddard Solvent (Varsol)at room temperature Soaped at 160 F. in 34% Soap 30 min. 4 hr. 6 hr. 2hr. 4 hr.

Sample #1---" 27 29 Sample #2 31 31 32 Example 2 3 parts by weight ofcetyl alcohol was dissolved in 7 parts by weight of ethyl alcohol byheating and the solution then cooled. This alcoholic solution was thenpoured with stirring into a dispersion of methylated methylol melaminecontaining 25 parts by weight of an 80% dispersion of methylatedmethylol melamine, 20 parts by weight of a solution of isopropylnaphthalene sulfonic acid and. 135 parts by weight of water. parts of a10% solution of diammonium hydrogen phosphate was then added to thedispersion. 80 x 80 cotton percale was impregnated with 11.5% of thedispersion (solids basis) by the dip and nip process. The fabric wasthen air-dried and cured four minutes at 290 F. After soaping for .5hours at 160 F. in a .5% soap solution the fabric was found to absorbonly 29.2% water when subjected to the spray test described in theprevious example.

What I claim is:

l. A method of finishing textile fabrics which comprises impregnatingthe textile fabric with an aqueous dispersion containing 2 to by weightof a mixture of a substantially unpolymerized, water-solublemethoxymethyl melamine containing at least two methoxymethyl groups andan aliphatic alcohol having at least 8 carbon atoms, said aliphaticalcohol being present in the dispersion in amounts corresponding toabout 0.5 part to 5.0 parts by weight for each 10 part by weight ofmethoxymethyl melamine, and thereafter heating the treated textile toinsolubilize the resin-forming constituents therein.

2. A method of finishing textile fabrics which comprises impregnatingthe textile fabric with an aqueous dispersion containing 2 to 15% byweight of a mixture of a substantially unpolymerized, water-solublemethoxymethyl melamine containing at least two methoxymethyl groups andoctadecyl alcohol, said octadecyl alcohol being present in thedispersion in amounts corresponding to about 0.5 part to 5.0 parts byweight for each 10 parts by weight of methoxymethyl melamine andthereafter heating the textile fabrics to insolubilize the resin-formingconstituents therein.

3. A method of finishing textiles which comprises impregnating thetextile fabric withln aqueous dispersion containing 2 to 15% by weightof a; mixture of a substantially unpoly- 5 merized, water-solublemethoxymethyl melamine containing at least two methoxymethyl groups andan aliphatic alcohol having at least 8 carbon atoms, said aliphaticalcohol being present in the dispersion in amounts corresponding toabout 10 0.5 to 5.0 parts by weight for each 10 parts by weight ofmethoxymethyl melamine and curing the resin-forming constituents withinthe range 200 F. to 300 F. to a water-insoluble state.

4. A textile finishing composition comprising an aqueous dispersion of asubstantially unpolymerized, water-soluble methoxymethyl melaminecontaining at least two methoxymethyl groups and dodecyl alcohol. saiddodecyl alcohol being present in the dispersion in amounts correspondingto about 0.5 part to 5.0 parts by weight for.

each 10 parts by weight of methoxymethyl melamine.

5. A textile finishing composition comprising an aqueous solution of awater-soluble methoxymethyl melamine containing at least two methaqueoussolution of a Water-soluble methoxymethyl melamine containing at leasttwo methoxymethyl groups, said solution having dispersa therein analiphatic alcohol having at least 8 car bon atoms in amounts of about0.5-5 part b:

weight for each 10 parts of the methoxymethy melamine.

7. A textile finishing composition comprisin; an aqueous solution of awater-soluble methoxy methyl melamine containing at least two methoxymethyl groups, said solution having disperse therein about 0.5-5parts by weight of octadec alcohol for each 10 parts of the methoxymeth;

melamine.

8. A method of finishing textile fabrics whici comprises impregnatingthe fabric with a com position comprising a dispersion of an aliphatialcohol of at least 8 carbon atoms in an aqueoisolution of awater-soluble methoxymeth5 melamine containing at least two methoxymethyl groups and thereafter heating the im pregnated fabric toinsolubilize the resin-form ing constituents therein.

. JOHN MARSHALL GRIM.

REFERENCES CITED The following references are of record in th file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,197,375 Widmer et al Apr. 16,194 FOREIGN PATENTS Number Country Date 486,577 Great Britain May 30,19:

OTHER REFERENCES Gams, British Plastics, pages 508-520, Feb. 19(corresponds to Helvetica Chemica Acta, vol. 2

P es 302E-319E; December 13, 1941.

